Yeah, I agree. This seems like it would be useful for stretches on 405, but not likely the bulk of a trip. Where I live, I could see it being useful for a decent chunk of 101, which could amount to 30 mins each way, each day.

I wonder if it drops down into a less-capable driver-assist mode when the speed goes higher, such that you can still just monitor the system for nearly all of your trip. Or does it drop you out into full human-driving mode?